For most households, a home is the largest asset they will ever own, and a mortgage is the largest debt they will ever carry. That makes housing different from almost any other market. When house prices rise or fall significantly, the effects reach far beyond buyers and sellers, shaping household spending, bank lending, construction activity, employment and the wider economy.
Housing booms have occurred in many countries over the past half century, and some have ended in painful busts. Others have simply levelled off, with prices stagnating for years while incomes caught up. Telling the difference in advance is difficult, and housing is a subject on which opinions run strong.
This article does not predict any particular housing market. Instead, it explains the forces that drive house prices, the measures used to judge whether a market is stretched, how housing booms have ended in the past, and what housing cycles mean for businesses. It is part of GoCore’s series on bubbles; the general warning signs are covered in Warning signs of a bubble.
Why housing is different
Housing differs from shares and most other assets in several important ways.
It is both a home and an investment. Most people buy housing primarily to live in, which makes demand less sensitive to price than for purely financial assets. But the investment element means that expectations of future price growth also influence decisions.
It is heavily financed with debt. Most home purchases are funded largely by mortgages, often for 70% to 90% of the price or more. That makes housing highly sensitive to interest rates and lending conditions.
It is local. A national housing market is really a collection of local markets with different supply, demand and prices. One city may be booming while another stagnates.
Supply responds slowly. Building new housing takes years, constrained by land availability, planning rules, construction capacity and infrastructure. When demand rises, prices often adjust long before supply can.
It is expensive to buy and sell. Transaction costs, such as stamp duty, agent fees and moving costs, discourage frequent trading and make the market less liquid than share markets.
What drives house prices
Several forces push house prices up or down, usually in combination.
Interest rates
Lower interest rates reduce monthly repayments for a given loan, allowing buyers to borrow more. When rates fall significantly, the amount buyers can afford rises, and prices tend to follow. This is one of the most powerful drivers of housing booms. Housing booms in several countries in the early 2000s were partly the result of low interest rates set to cushion economies after the technology share bubble burst.
Credit availability
Beyond the interest rate, the availability of credit matters: deposit requirements, the maximum loan relative to income, the treatment of investors and interest-only loans, and the number of lenders competing for business. Loosening credit standards allows buyers to pay higher prices. The article Credit: the fuel behind every bubble explains this dynamic.
Population and household growth
More households need more homes. Population growth through births, migration and changes in household size raises demand. Housing booms in countries such as the United Kingdom and Australia in the early 2000s were often linked to increased immigration. These are real influences, though they can be used to justify price rises far beyond what population growth alone would explain.
Incomes
Rising incomes allow households to afford more. Over the long run, house prices and incomes are connected, because buyers must be able to service their loans from their incomes.
Supply
Where new supply is constrained by land, planning rules or construction capacity, rising demand pushes up prices rather than producing more homes. Where supply responds quickly, booms tend to be more moderate, though they can still produce overbuilding.
Tax settings
Tax rules affect the attractiveness of housing as an investment. In Australia, for example, the ability of property investors to deduct net rental losses against other income, known as negative gearing, and the 50% capital gains tax discount for assets held longer than a year, are frequently discussed as influences on investor demand. Their size and effect are debated, and they can change, so current rules should be checked with an adviser or the Australian Taxation Office.
Expectations
Finally, expectations of future price growth influence decisions. If buyers expect prices to keep rising, they are willing to pay more today and to borrow more to do so. Expectations can be self-reinforcing during booms, and self-defeating during busts.
Measures for judging a housing market
Price-to-income ratio
The price-to-income ratio compares typical house prices with typical household incomes. A rising ratio means buyers must borrow more relative to their incomes, making the market more dependent on low interest rates and easy credit. Comparing the ratio with its own history, and with other cities and countries, gives a sense of how stretched a market is.
Rental yield
The rental yield is the annual rent a property could earn divided by its price. When prices rise much faster than rents, yields fall. Very low yields mean that housing as an investment relies heavily on future price gains rather than on the rent it produces.
Repayments as a share of income
Because interest rates change, the price-to-income ratio alone can mislead. The share of income needed to service a typical new mortgage combines price, income and interest rates into a single measure of affordability. It shows how vulnerable buyers would be to a rise in rates.
Credit growth and household debt
Rapid growth in housing credit, and rising household debt relative to income, show how much of the boom is financed by borrowing. High household debt leaves the economy more vulnerable to rising interest rates and falling prices.
Construction and supply
Rising construction activity can indicate that supply is responding to demand, which may moderate prices. Very high construction relative to population growth can signal future oversupply, especially in particular segments such as inner-city apartments.
Investor share and lending types
A rising share of loans to investors, or to borrowers taking interest-only loans, suggests that expectations of price growth, rather than the need for a home, are driving more of the market.
How housing booms end
Housing booms do not always end in crashes. Several outcomes are possible.
A long plateau. Prices stop rising and drift sideways or fall slightly in real terms for years, while incomes catch up. Affordability gradually improves without a sharp fall.
A moderate correction. Prices fall by a modest amount, often in response to rising interest rates or tighter credit, then stabilise.
A severe bust. Prices fall sharply, often after a period of very rapid credit growth, loose lending and overbuilding. Severe busts can damage banks and the wider economy.
The US housing bust that began around 2006–07 is the most prominent recent example of a severe bust. It was preceded by very loose lending, including loans to borrowers with poor credit and little ability to repay, and by complex financial products that spread mortgage risk through the global financial system. Its collapse triggered the global financial crisis.
Housing busts in the United Kingdom and Scandinavia in the late 1980s and early 1990s followed periods of financial deregulation and rapid credit growth. Japan’s property bubble, which burst around 1990, was followed by many years of falling land prices.
Triggers
Common triggers for housing corrections include rising interest rates, tighter lending rules, economic downturns that increase unemployment, and oversupply as new construction is completed. Because housing is heavily indebted, rising unemployment is especially dangerous: borrowers who lose their jobs may be forced to sell, adding to supply when demand is weak.
Busts are not only about prices
Housing downturns are often discussed only in terms of prices, but activity usually falls first and furthest. When conditions turn, the number of sales drops sharply as buyers wait and sellers hold out for previous prices. Building approvals and new construction fall. Mortgage lending slows. These changes in volume hit agents, builders, brokers, tradespeople and suppliers well before any large fall in prices appears in the headlines, and they can persist even if prices fall only modestly.
For businesses linked to housing, transaction volumes and construction activity are therefore often better guides than prices. A market in which prices hold steady but sales fall by a third can be very difficult for the businesses that depend on activity.
Policy and housing
Policymakers have several tools to influence housing booms.
Central banks set interest rates, though they usually target inflation and employment rather than house prices directly. Prudential regulators can set rules for lenders, such as limits on high loan-to-value lending or loans relative to income, and requirements to test borrowers’ ability to repay at higher interest rates. In Australia, the prudential regulator APRA used measures of this kind during the 2010s to slow growth in investor and interest-only lending. Governments can influence supply through planning and infrastructure, and demand through tax settings and migration policy.
What housing cycles mean for businesses
Housing cycles affect a wide range of businesses.
Directly linked businesses. Builders, tradespeople, building-materials suppliers, real estate agents, mortgage brokers, conveyancers, furniture and appliance retailers, and removalists all depend on housing activity. Their demand rises and falls with the cycle, often sharply.
Wealth-sensitive businesses. When house prices rise, homeowners feel wealthier and may spend more on renovations, cars, travel and dining. When prices fall, that spending can contract. The article Wealth effects explains the mechanism.
Business owners as homeowners. Many small businesses are funded through loans secured against the owner’s home. Rising prices increase borrowing capacity; falling prices can reduce it just when the business needs support.
Staff and costs. High housing costs in a city affect the wages businesses must pay, their ability to attract staff and the cost of premises.
Practical steps
- Understand how much of your demand depends on housing activity or homeowners’ sense of wealth.
- Watch leading indicators, such as interest rates, lending conditions, building approvals and auction clearance rates where relevant.
- Plan capacity for an ordinary year rather than for the peak of a housing boom.
- Be cautious about relying on home equity to fund the business.
- Diversify towards customers whose demand is less sensitive to the housing cycle, such as repair and maintenance work rather than only new building.
A worked illustration
This is an illustration with round numbers.
A household earns $150,000 a year before tax and buys a home for $900,000, a price-to-income ratio of 6. With a 20% deposit, it borrows $720,000.
| Interest rate | Approximate annual repayment (30-year loan) | Share of gross income |
|---|---|---|
| 3% | about $36,400 | about 24% |
| 5% | about $46,400 | about 31% |
| 7% | about $57,500 | about 38% |
A rise in interest rates from 3% to 7% increases repayments by more than half. A household that bought when rates were low, borrowing the maximum it could, would face serious pressure if rates rose significantly. Multiply that across a market, and it becomes clear why housing is so sensitive to interest rates and why high household debt increases the risk of a correction.
Common mistakes
Treating housing as one national market. Conditions differ greatly between cities and segments.
Assuming prices can only rise. History includes long plateaus and severe busts.
Ignoring interest-rate sensitivity. Affordability depends heavily on rates.
Dismissing real drivers. Population, incomes and supply genuinely matter; the question is whether prices have moved beyond them.
Overlooking the business impact. Many businesses are exposed to housing cycles indirectly.
Questions to ask
- How do price-to-income ratios and rental yields compare with history in this market?
- How much of the boom is financed by credit, and how fast is housing credit growing?
- How sensitive are buyers to rising interest rates?
- Is supply responding, and could it create oversupply in some segments?
- For your own business: how much of your demand, funding or costs depends on the housing market?
Bringing it together
Housing is unlike other markets: it is both a home and an investment, heavily financed with debt, local, slow to adjust in supply and costly to trade. Prices are driven by interest rates, credit availability, population, incomes, supply, tax settings and expectations, usually in combination.
Measures such as price-to-income ratios, rental yields, repayment burdens and credit growth help judge how stretched a market has become. Housing booms can end in plateaus, corrections or severe busts, depending largely on how much debt financed them. For businesses, understanding exposure to the housing cycle, through customers, wealth effects, funding and costs, is an important part of planning for both good times and bad.
Sources: an introductory chapter on asset bubbles written in the mid-2000s and widely documented economic history. Figures in the worked illustration are approximate and illustrative. Tax and lending rules change; check current rules with a qualified adviser. This article is general information, not financial, tax or investment advice.
